The present invention relates to a method for fabricating semiconductor devices. More particularly, the present invention relates to an improved method for forming chip patterns which prevents the devices from contamination caused by residues of removed patterns which are etched off by a photolithographic process.
One important factor which has a substantial effect on the production yield of semiconductor devices is contamination. Most of the semiconductor devices are fabricated in a clean room or on a laminar flow bench in which filtered air flows to remove dust floating in the air. As the integration rate in a semiconductor chip increases, the problem of dust rejection became more severe. Thus all of the integrated circuit (IC) chips are now fabricated in a super clean room.
The contamination rejection is performed thoroughly and as completely as possible in all of the production steps, equipment, materials, chemicals and water used in production. But production still often suffers from contamination, and the yield is thus affected. This trend is becoming severe, and thus can not be ignored in the production of large scale integration (LSI) circuits.